1) The largest living structure on Earth is the Great Barrier Reef, spanning over 2,300 kilometers (1,400 miles) along the coast of Australia.

2) Democracy is a system of government in which power is vested in the people, who exercise it through elected representatives. It allows for political participation, freedom of speech, and protection of individual rights and liberties.

3) The word "computer" contains three vowels: O, U, and E.

4) The sport of golf originated in Scotland and is played on courses with 18 holes, each with a designated par score.